Early in my career, I thought polyrepos were the way. Microservices, each in their own repo, independently deployable — it felt clean and modern. Then I joined Meta and worked in their massive monorepo, and it changed how I think about code organization entirely. Anything I needed to change, I could change it right there. Everything was discoverable. One commit could do everything I needed it to. Then I moved to AWS, back to polyrepo land, and the contrast was painful. Now I'm building my own...